From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailsec114.isp.belgacom.be ([195.238.20.110]:25110 "EHLO mailsec114.isp.belgacom.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751437AbcKYGOf (ORCPT ); Fri, 25 Nov 2016 01:14:35 -0500 Date: Fri, 25 Nov 2016 07:14:33 +0100 (CET) From: Fabian Frederick Reply-To: Fabian Frederick To: Theodore Ts'o Cc: linux-kernel@vger.kernel.org, Alexander Viro , Jan Kara , linux-fsdevel@vger.kernel.org Message-ID: <729028918.362386.1480054473313.open-xchange@webmail.nmp.proximus.be> In-Reply-To: <20161125052639.3v56ef3clt7r52hr@thunk.org> References: <1480016861-24432-1-git-send-email-fabf@skynet.be> <20161125052639.3v56ef3clt7r52hr@thunk.org> Subject: Re: [PATCH 1/1 linux-next] ext4: add compatibility flag check MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-fsdevel-owner@vger.kernel.org List-ID: > On 25 November 2016 at 06:26 Theodore Ts'o wrote: > > > On Thu, Nov 24, 2016 at 08:47:41PM +0100, Fabian Frederick wrote: > > data=journal mount option should disable O_DIRECT access > > (See Documentation/filesystems/ext4.txt) but open operations > > using O_CREAT|O_RDWR|O_DIRECT|O_SYNC have no warning in return and file is > > being > > created. This patch adds vfs super_operations compatibility flag function > > returning -EPERM in such a case. > > > > Signed-off-by: Fabian Frederick > > The general practice by most file systems in Linux (for better or for > worse) is to silently fall back to buffered I/O instead of failing the > O_DIRECT open.  Feel free to try to convince linux-fsdevel otherwise, > but that is the general and historical consensus of Linux file system > developers. > > Cheers, Thanks a lot Ted, I'll have a closer look at vfs/ext4 documentation and add some details if required. Regards, Fabian > >                                       - Ted